Method of and machine for erecting long straggling subterraneous buildings

ABSTRACT

Proposed is a method of erecting long straggling subterraneous buildings within an open ditch, comprising the steps of excavating the earth at the end face of the ditch by means of a digging machine which is advanced substantially continuously, supporting the lateral walls of the ditch in the region adjacent the end face by prop pieces which are moved forward together with the digging machine, sectionwise building-in the building from prefabricated parts directly behind the digging machine in the free space between the prop pieces at the bottom of the ditch, supporting the lateral walls of the ditch in a region located behind the prop pieces, and subsequently filling the ditch again over the building.

United States Patent Morner 14 1 Jan. 25, 1972 METHOD OF AND MACHINE FOR ERECTING LONG STRAGGLING 211 App]. No.: 749,384

[52] U.S. Cl ..6l/4l [51 Int. Cl. 1 1 ..E02f 5/06 [58] Field of Search ..6l/4l.l, 72.2, 72.5, 72.7,

6l/4l, 85; 37/86, 86 A, 87

1,164,072 12/1915 'Crall ..6l/41UX 1,234,716 7/1917 Bager .61 4 11 1,267,058 5/1918 Clarkson ..6l/4l UX 1,723,691 8/1929 Farrar .37/86 3,292,379- 12/1966 McElvany ..6l/72.5

Primary Examiner-Dennis L. Taylor Anomey-Joseph Weingarten [57] ABSTRACT Proposed is a method of erecting long straggling subterraneous buildings within an open ditch, comprising the steps ofexcavating the earth at the end face of the ditch by means of a digging machine which is advanced substantially continuously, supporting the lateral walls of the ditch in the region adjacent the end face by prop pieces which are moved forward together with the digging machine, sectionwise building-in the building from prefabricated parts directly behind the digging machine in the free space between the prop pieces at the bottom of the ditch, supporting the lateral walls of the ditch in a region located behind the prop pieces, and subsequently filling the ditch again over the building.

6 Claimsf 13 Drawing Figures PATENTED M25 I972 SHEEI 1 BF 8 INVENTOR JOHANN MORNER ATTORNEYS PAILNltUJANZbISIZ 3.636.715

I sum 2 or 8 INVENTOR OHANN MORNER ATTORNEYS PATENTEB #3425 m2 SHEU 4 0F 8 INVI E NTOR JOHANN MORNER mm w lllll Y X 3 9R ATTORNEYS PATENTEU JANZSI'JYZ 3'638'715 SHEET 5 0F 8 JOHANN MORNER ATTORNEYS PATENTED JAN 2 512172 SHEET 6 [IF 8 Fig. 6b

Fig. 60

at/5w"; JOHANN MORNE F Y 5 .m ATTORNEYS PATENTED JANZS I972 SHEET 8 OF 8 2 ATTORNEYS METHOD OF AND MACHINE FOR ERECTING LONG STRAGGLING SUBTERRANEOUS BUILDINGS BACKGROUND OF THE INVENTION This invention relates to a method of, and a device for erecting long straggling subterraneous buildings underneath vacant plots, wherein a ditch which is open toward the earth surface is excavated.

It is known to construct buildings of this type in that the ditch walls are secured by means of vertical steel props and planks located therebetween, as well as by means of stifi'eners or braces which support the walls of the ditch. Between this built-up part, the ditch is then excavated by means of bulldozers and dredgers, whereupon the building is erected, mostly in site concrete. The assembling and disassembling of the here briefly described building-up part and the erection of the construction in concrete in situ necessitate a high expenditure of work and hence a correspondingly long time of construction. Yet a long time of construction is disadvantageous in many respects-because, e.g., it causes increased buildup costs, a correspondingly long, necessary subsoil water lowering, and a long-range impediment of the traffic and of the neighbors. The utilization of prefabricated parts in conjunction with said known method is very complicated because of the obstruction of the stifieners. It was heretofore impossible to achieve a better rationalization by using prefabricated parts enclosing the entire cross section of the building, in lieu of the concrete construction in situ.

SUMMARY OF THE INVENTION Thus an object of this invention is to provide a method of erecting long straggling subterraneous buildings within an open ditch, which is suited to a high degree for using prefabricated parts and which permits a more rapid, more rationalized and more economical realization of the building.

Another object of the invention is to provide a method of the above-mentioned kind, wherein a perfect mechanization of the building process is achieved by employing a special equipment and by using prefabricated parts.

This and further objects are achieved according to the invention by a method of erecting long straggling subterraneous constructions within an open ditch, comprising the following steps:

Excavating the earth at the front side of the ditch for the construction by means of a substantially continually advanced excavating machine;

propping the sidewalls of the ditch for the building in the region adjacent the end face by means of prop members which are forwardly moved along with the excavator machine;

building-in the construction sectionwise from prefabricated parts on the bottom of the ditch substantially within the free space interposed between the prop members;

propping the sidewalls of the ditch in a ditch section lying behind the prop members; and

refilling the ditch above the construction.

It is to be noted that in the description hereinafter and in the attached claims, a substantially continuously advanced excavator machine also implies a machine which is advanced in regular, relatively short time intervals, by determined lengths corresponding to the advance of the winning.

According to the invention, the propping of the sidewalls of the ditch in the region from the worked gallery sole to the height of the building can take place in that the space which becomes free behind the prop members subsequent to the advanced digger between the ditch wall and the building, as well as that in the region above the building are immediately filled up by means of vertical steel planks, the lower ends of which are detachably secured to the ditch walls by means of elements supported on portions of the building, while the upper ends thereof are secured to the ditch walls across the ditch to the steel planks of the respectively opposite side of the ditch.

Furthermore, the invention provides a machine for erecting long straggling subterraneous constructions within an open ditch, which contains means for digging the earth at the front face of the ditch, driving means for moving the machine in the direction of advance, and wall elements for supporting the sidewalls of the ditch in the region adjacent the front side, so that in the shield of these wall elements it becomes possible to erect the building sectionwise from prefabricated parts.

Thus it becomes apparent that a continuous drive-on of the ditch is possible. Immediately upon the build-in of the prefabricated parts, the ditch is refilled above the erected building so that the ditch can be kept short and only a small stock of steel planks must be kept in store.

The excavation of the soil at the front face of the ditch may take place by endless bucket chains arranged across the whole width of the ditch or by means of scraper buckets which are likewise arranged across the whole breadth of the ditch However, according to an alternative embodiment, the excavation can be performed also by means of at least one bucket chain arranged on the excavator machine for movement transversely to the drive-on direction of the ditch.

The drive elements for the forward movement of the excavating machine are preferably in the form of hydraulic presses which are either arranged on the excavating machine at both sides along the walls of the ditch and abut said steel planks as well as portions of the building or projecting away from the excavating machine mainly in a row extending transversely to the longitudinal plane of the ditch, said presses also engaging with the roof of the building. In the latter case, the excavating machine may be maintained stable in position and, in addition, easily guided over ascents or descents by means of a few presses arranged in the region of the floor of the ditch and in the region of the earth surface.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will become apparent from the detailed description of illustrative embodiments with reference to particular advantages and important features as well as to the accompanying drawings, in which:

FIG. 1 is a longitudinal sectional view of a ditch for driving a tunnel according to the method of the invention;

FIG. 2 is a cross-sectional view of the ditch of FIG. 1 and illustrating an already built-in portion of the building, and a building section ready for insertion by means of a gantry crane; beam-generating beam-generating FIG. 3 is a schematically simplified plan view of the ditch of FIG. 1;

FIGS. 41: and 4b are horizontal sectional views of details of the walls of an excavating machine according to the present invention;

FIG. 5 is an enlarged detail of the cross-sectional view of FIG. 2 for illustrating the structure of a joint of a prefabricated part dismountable according to the invention, as well as for elucidating the propping of the foot point of a steel plank;

FIGS. 60 to 6d are two alternative embodiments of the digging device of the excavator according to the present invention;

FIG. 7 is a sectional view partially corresponding to FIG. 1 for illustrating another embodiment of the digging device, wherein the bucket chain is arranged for movement transversely of the ditch;

FIG. 8 is a schematical plan view of another embodiment of the excavating machine according to the invention, including a pair of bucket chains arranged for movement transversely of the ditch and also movable in the drive-on direction, as well as a modified embodiment of the drive means for the forward movement of the excavating machine; and

FIG. 9 is a sectional view similar to FIG. 1 for illustrating another modified embodiment of the present invention, wherein the ditch for the building is driven on at the front side in two sections of height.

DETAILED DESCRIPTION As shown in particular in FIGS. 1 and 3 of the drawings, a ditch l for the building is excavated by means of the excavating machine generally designated by 2 according to the invention in that the soil or earth 3 appearing on the surface is excavated at the front face in a continuous drive-on. At the same time, the front side of the ditch for the building is maintained inclined according to the stability of the soil concerned. The digging device 2 has lateral wall-like prop members 2 and 2" which extend rearwardly from the front of the ditch and which have the task to secure the ditch walls rearwardly from the ditch front so far that whole building sections can be inserted under the protection by the rearward portion of the machine according to the invention, as will be discussed in greater detail hereinafter. The earth 3 is broken loose by means of bucket chains 4 which are arranged across the whole breadth of the ditch according to the embodiment of the present invention shown in FIG. 1. The bucket chains 4 feed the earth into transverse conveyor belts 5 which convey the earth to longitudinal conveyor belts 6 which in turn serve for loading the trucks 7a and 7b. The longitudinal conveyor belts 6 are adapted to travel in a manner which is not shown in detail in v the drawings so as to permit to carry them along according to the advance of the building and to control the delivery of the soil to one or the other of the longitudinal conveyor belts by a simple longitudinal displacement.

For the advance of the excavating machine according to the invention are used hydraulic presses 8 which, in the just described embodiment of the excavating machine, are installed in or adjacent the walls of the machine so that they can abut steel planks 9 in the region above the building to be erected, while in the range of the building they can abut prefabricated parts 10 utilized for building the construction.

When the ditch l for the building is driven-on a determined length, then a further prefabricated part 10 will be carried along from an assembly station (not shown) located ahead of the site of building by means of a gantry crane l1 movable on rails 11- and 11" shown in FIG. 3 and located at both sides of the ditch, whereupon the prefabricated part 10 is inserted into the ditch for the building, as shown in FIGS. 1 and 2 of the drawings.

The areas of the sidewalls of the ditch that are designated by 12 in FIGS. 2 and 5 and become free during the drive-on of the excavating machine are secured within the range of the building in that the space 13 cleared between the ditch walls and the prefabricated parts is refilled immediately, which, for example, may be accomplished by means of well-plastical concrete. In the region lying thereabove the propping is effected with the aid of the already mentioned vertical steel planks 9 which, built-in closely adjacent each other in a slight spaced-apart relationship, are supported against each other at the upper ends by means of stiffenings 14, and against the prefabricated parts 10 at the foot point by means of hard wood props 15, as is readily apparent from FIGS. 2 and 5.

In the rearward region 18 of the ditch 1, the steel planks 9 are drawn by means of a further gantry crane 19 running on the same rails as the gantry crane 11, while at the same time the hollow spaces 20 resulting thereby are filled up with suitable material, wherefor the gantry crane 19 is utilized again. The material used for refilling may be compacted by, e.g., the shaker 28 which is hung up in the steel planks 9. After drawing the steel planks 9, they are forwarded to the excavating machine 2 and inserted anew. Besides, the gantry crane 19 serves for dismounting, moving and reinserting the stiffenings 14.

Both gantry cranes are constructed so broad, and the rails 11' and l l" are placed so remote from the border of the ditch that the trucks 7 used for transportation of the earth can travel between the ditch border and the rails so that neither the transport of the earth nor the path of the cranes is interfered with. The thus resulting great clear span of the cranes also facilitates the overtravel of railway station building sites, while the transportation of the whole equipment must take place beyond such places that interrupt the normal line location. To this end, the carrying capacity of the gantry cranes 1 l and 19 is selected so that in tandem-operation they can lift and move the entire excavating machine 2 according to the invention.

While the hollow spaces 20 which, as already mentioned, become free upon drawing the steel planks 9 are filled up with material adapted to be compacted by means of the shakers 28 so that no subsidings can appear in the adjacent regions, the ditch l is refilled, commencing directly behind the last-inserted prefabricated part 10, in the form of a slopping terrace or ramp 21 advantageously using the earth removed by means of the trucks 7a from the rearward loading stations for the refilling, whereby achieving the shortest ways for transport. The ramp 21 can have a maximum inclination such that the bulldozers 22 and the surface shakers 23 can still move upwards safely, which shakers serve for compacting the earth tilted-off by the trucks 7a at the rear side 18 of the ditch, which earth is transferred according to FIG. 3 of the drawings by means of the conveyor belts 5 and 6 in the direction of the respective arrow.

In the relatively simple embodiment of the invention shown in FIGS. 1 to 3 of the drawings, the wall-like prop members 2'- and 2" of the excavating machine according to the invention are located directly adjacent the ditch walls so that preferably straight lines can be built by this excavating machine. However, if curvatures must be performed, then a modified embodiment of the excavating machine according to the present invention partially shown in FIGS. 4a and 4b is preferably used, wherein the wall-like prop elements are formed so that between the sidewalls 12 of the ditch and the excavating machine 2 there can be arranged a layer of thixotropic fluid 24 which is sealed off by an edge 25 at the front of the ditch and by a resilient seal 26 at the end of the excavator machine. The seal 26 encloses a space 27 which is closed in a pressureproof manner and which is also filled with a thixotropic liquid and, in addition, loaded with compressed air, so that the seal 26 firmly engages the ditch wall 12. A lateral displacement of the excavating machine 2 and hence the drive-out of curvatures is facilitated by this arrangement while moreover there is achieved the advantage that the friction occurring during the drive-on of the excavating machine is minimized quite essentially. In the present case, the thixotropic liquid may be used in a thick-fluid state, which facilitates the sealing off. A further advantage of a thixotropic liquid layer 24 between the excavating machine 2 and the ditch wall 12 is the increase of the slideability of the steel planks 9 due to a residual liquid on the ditch walls so that the steel planks 9 can later on be readily drawn.

In addition, a further advantageous feature of the embodiment of the excavating machine according to. the invention as is described with reference to FIGS. 4a and 4b can be learned from these Figures. In this embodiment, a drag plate 16 of sheet stock is arranged as an extension of the resilient seal 26 adjacent the latter. When the excavating machine is driven-on in a soil in which a clearing of the sidewalls of the ditch along a short portion cannot be permitted for a short time, then the steel planks 9 are inserted here at both sides to the drag plates 16 which, during the forward drive of the excavating machine 2, will then draw themselves out behind the last-inserted steel planks. Thereupon the stiffenings l4 and the hard wood props 15 will be readjusted. The loading and unloading of the stiffenings 14 will then take place by hydraulic or screw presses 17 provided on the end of said stiffenings.

The above-mentioned bucket chains 4 for digging the earth at the front side of the ditch are represented in their details in FIGS. 6a and 6b. The bucket chains are arranged across the entire breadth of the ditch and consist'of main chains 4a and secondary chains 4b, while the buckets of the individual chains are offset relative to each other so that they can be telescoped in the downwardly extending region shown in FIG. 1, and they can run downwardly on the breadth reduced by the dimension of the walls 2 and 2" as well as the adjacent presses. The buckets of the main chains 40 are screwed on at traction cables 33 and guided by guides 34, while the buckets of the secondary chains 4b are hung up in between the main chains 4a. The bucket chains permit a simultaneous removal of the soil along the entire cross section of the ditch.

However, if foreign matter is frequently present in the range of the ditch, such as rock deposits, old channels etc., which can no longer be broken and carried away by the buckets of the bucket chains 4, then scraper buckets 35 which are likewise arranged across the entire breadth of the ditch may be used in accordance with a modified embodiment of the excavator according to the present invention as shown in FIGS. 60 and 6d. The scraper buckets 35 run up and down only on the front side 3 of the ditch and are guided on guides 36. The scraper buckets 35 are emptied in that their bottoms 37 are opened whereby the dug earth drops onto transverse conveyor belts which correspond to the conveyor belts 5 and which are not shown in detail yet which in this case are arranged in front of the excavator 2 according to the present invention. The scraper buckets 35 can be constructed considerably larger and robuster than the buckets of the bucket chains so that they have a greater breaking power and can carry larger individual pieces, too.

However, in certain cases the technical expenditure required for the bucket chains or scraper buckets arranged transversely over the ditch breadth may be unduly great, and it may be not always possible to utilize the high haulage capacity of such excavating equipments. Besides, some obstructions in the soil, for example rock deposits, may not be removed without difficulties, because in the embodiment of the excavating machine described so far in accordance with the present invention the entire front of the ditch is covered by the digging means. That is why in accordance with a further modified embodiment of the invention as is represented in FIGS. 7 and 8, only one or two bucket chains 40 and/or 40a which are adapted to be sidewise displaced and pivoted are proposed here in lieu of the bucket chains or scraper buckets arranged across the whole width of the ditch for the building. The bucket chain 40 of the excavator of FIG. 7 of the drawings according to the present invention or the bucket chains 40 and 400, respectively, of the embodiment according to FIG. 8 comprising two transversely movable bucket chains arranged side by side in turn feed the removed earth to a conveyor belt designated by 50 in FIG. 7. The bucket chain 40 or the bucket chains 40 and 400, respectively, are mounted by means of rollers on support rails 51 and on guide rails 52 so that in respect to the embodiment according to the invention as shown in FIG. 7 they can be reciprocated across the whole breadth of the ditch, and with respect to the embodiment according to FIG. 8-across one-half of the breadth of the ditch. The carrying rails 51 carry the weight of the bucket chain concerned and the reaction forces appearing during operation, while the guide rails 52 serve for ensuring the requisite inclined position of the bucket chain 40 or of the bucket chains 40 and 400, respectively. The carrying rails 51 and the guide rails 52 are mounted on the excavator 2 according to the present invention in a manner not shown in detail in the drawings so that they can be displaced in the drive-on direction by one working depth of the bucket chain(s). Due to this longitudinal movability of the bucket chain(s) along the excavator, it is achieved that an advance of the respective bucket chain can take place also without moving the excavating machine whereby the number of advance phases of the excavator can be reduced. The lateral movement of the bucket chains may take place by means of cable winches (not shown).

The mode of operation of the embodiment of the excavating machine comprising two bucket chains 40 and 40a guided symmetrically to the center axis according to the present invention can be easily learned from FIG. 8 of the drawings. The left-hand portion of FIG. 8 shows the position of the respective bucket chains 40 and 40a during the first operational step upon the advance of the excavating machine 2. First of all, the

bucket chains 40 and 40a are pivoted at opposite sides from the positions A into the inclined position according to position B and then laterally moved toward each other in the direction of the center of the ditch and brought there into the position C. When both bucket chains have reached this position, they will be displaced forwardly by advancing the carrying rails 51 and the guide rails 52 one working depth so that they will come into a position corresponding to the position D. The right-hand side of FIG. 8 shows the situation during the second operative step after the advance of the excavating machine. The bucket chains 40 and 40a will now be pivoted apart from each other from the position D into a position corresponding to the position E and subsequently moved laterally up into the position F. As soon as both bucket chains 40 AND 40a have reached a position corresponding to the position F, the excavating machine 2 will be advanced two working depths of the bucket chains. Thereafter the bucket chains will be withdrawn into the position A, and the excavation of the soil will be continued in a new cycle. The respective inclined position of the bucket chains 40 and 40a is achieved in that the mutual spacing between the carrying rollers 51a running on the carrying rails 51 and the guide rollers 52a running on the guide rails 52 is adjusted by suitable means with which the man skilled in the art is familiar. As a particular advantage of the just described digging device of the excavating machine according to the invention is to be regarded that in contradistinction from the embodiment described at the outset hereinabove, only a by far lesser number of buckets is necessary here so that the haulage capacity can be utilized to the full. Also, obstructions in the soil appearing on the surface can be easily removed because the entire front side of the ditch is accessible.

Now if merely one portion of the entire excavated earth is suited for refilling the ditch for the building, and if the individual soil kinds are substantially in the same height of layers, then an embodiment of the excavating machine according to the present invention as is schematically shown in FIG. 9 finds utilization, wherein in the upper region there the parts 53 of the lateral wall-like prop elements 2' and 2" are drawn forward so far that also a second bucket chain 55 can be arranged in front of a bucket chain 54 extending up to the sole of the ditch. Thus it is possible to excavate an upper soil layer 3a by means of the forward, shorter bucket chain 55, and a lower soil layer 3b by means of the bucket chain 54 separately from each other.

The embodiments of the excavating machine according to the invention as elucidated in conjunction with FIGS. 7 to 9 of the drawings, as compared with the embodiment described at the outset hereinabove, show a remarkable difference with respect to the arrangement of the drive means for the advancing of the excavating machine. Whereas the hydraulic presses 8 of the initially described embodiment substantially engage along the wall-like side props 2' and 2 so that the control of the presses distributed along the entire height is difficult, and especially an interruption of the advance is necessary when inserting the steel planks, hydraulic presses 56 in the lastdescribed embodiments are arranged side by side on an intermediate platform 57 so that they can be supported against the roof of the building 10 to be erected. Of course this arrangement of the presses is advantageous for all embodiments.

The pistons 58 of the presses 56 are firmly connected to a pressure beam 59 which is arranged for movement in the prop members 2 and 2", respectively, in a manner shown in FIG. 8. The pressure beam 59 distributes the pressure force of the presses to the concrete of the roof of the building and, due to the guidance in the members 2 and 2", also supports the press pistons in the case of a great overhand. Since the roof of the building coming into the question is located substantially in the middle region of the depth of the ditch, the presses 56 arranged transversely side by side permit that a great part of the entire advance force is exerted so that solely a few presses 60 mounted in or on the lateral prop members 2 and 2" in the upper and lower region of the excavating machine are necessary for controlling the latter with respect to height. The roof of the building constitutes an ideal abutment for the presses, while in viewof the fact that the advance force is transmitted to the excavating machine substantially in only two horizontal planes, it is possible to achieve a simplification of the control of the advance presses and thus of the excavating machine.

The prefabricated parts are preferably built in as complete building sections, as shown in FIG. 1 and FIG. 2 of the drawings, so that, a rapid and rational building performance can be achieved. If the transport of the entire building sections by roadway is impossible because of too large dimensions of these sections, then the prefabricated parts will be work concreted as whole building sections indeed, yet steel sheets 30 anchored at one side will be conjointly concreted along with the work concreting, so that joints 29 will be formed at the desired locations, along which the building sections 10 can be divided into individual parts 10a and 10b for the roadway transportation, as shown in FIG. 5 of the drawings. Thanks to the conjoint concreting, a perfect dimensional accuracy is achieved in the joints so that the individual parts can become dry at the assembly station located in the tunnel road in front of the ditch for the building, so that they can be clamped together in a short time by means of clamping members 31 while at the same time the joints 29 can become fully effective in statical respect. The projections 32 serve for transmitting the transverse forces. The prefabricated parts which are clamped together will be transported by means of the gantry crane 11 to the build-in site and then built in therein. Advantageously the individual parts of the respective fabricated building section consist of prestressed concrete.

'For protecting the building site against unfavorable weather, it is possible, due to the small longitudinal extension of the ditch for the building, to provide a movable tent 38 shown in FIG. 2, which is adapted to travel on rails and under which the gantry cranes Hand 19 can travel.

The technical and economical advantagesachievable by the present invention are based substantially on the full mechanization for the erectionof long straggling subterraneous works. The use of prefabricated parts permits a rapid and rational erection of the building from high-quality, optionally prestressed concrete. Advantages over the known building techniques involving an open ditch follow also from the fact that no buildup is necessary any more in the building range, while the ditch walls located above the building can be rationally built up by vertical steel planks, and the ditch can be immediately refilled at the rear side.

Hence it will be apparent that the invention is effective to reduce the costs for wages and allowances, the subsoil water lowering, and the impediment to the street-traffic and the neighboring traffic, so that the total costs to be taken into consideration are considerably decreased.

Many possibilities of modification of the exemplary embodiments described hereinabove offer themselves to those skilled in the art, which, however, come within the scope of the appended claims.

What is claimed is:

1. Method for erecting a long straggling subterraneous construction within an open ditch comprising the steps of:

excavating the earth at the front end of said ditch by means of a substantially continuously advanced excavating machine;

propping the sidewalls of said ditch in the region adjacent and extending rearwardly from said front end by means of prop members on either side of said ditch, said prop members extending rearwardly from said excavating machine a predetermined distance and attached to said excavating machine for forward movement therewith; forming said construction sectionwise from prefabricated sections on the bottom of said ditch substantially within the free space interposed between said prop members, filling the space between the respective sidewalls of said ditch and said construction to thereby support the sidewalls of said ditch behind said prop members in the region from the bottom said ditch to the height of said construction, said space being formed behind said prop members as said excavating machine moves forward;

inserting removable vertical planks along said sidewalls above said construction to thereby support said sidewalls of said ditch in the region from the top of said construction to the top of said ditch; and

refilling the ditch above the construction.

2. The method recited in claim 1 and further comprising the steps of:

wedging the bottom ends of said vertical planks against the top of said construction; and

bracing said planks adjacent the top of said ditch by means of stiffening members extending across said ditch between opposite sets of planks.

3. The method recited in claim 2 and further comprising the steps of:

removing said planks in the rearward regions of said ditch after said refilling step has been accomplished;

filling the hollow spaces resulting from the removal of said planks; and

transporting said planks forward toa position behind said excavating machine for reuse.

4'. The method recited in claim 1 wherein said refilling step is carried out substantially continuously in accordance with the advancement of said excavating machine in the form of a ramp sloping from the rearward end of said ditch toward said front end of said ditch.

5. The method recited in claim 1 and further comprising the steps of:

prefabricating disassemblable sections of said construction at a location remote from said ditch; disassembling said construction sections into more easily transportable elements;

transporting said elements to an assembly station in the vicinity of said ditch; nd

reassembling said parts to form prefabricated sections of said construction in preparation for the step of forming said construction in said ditch.

6. Method in accordance with claim 1 in which said propping of the sidewalls of the ditch in the region rearwardly of a ditch section lying behind the prop members is arranged at least in a region of the ditch lying above said construction by means of vertical planks the lower ends of which are secured against the sidewalls of the ditch taking abutment on parts of the construction and the upper ends of which are secured against the sidewalls of the ditch by means of stiffening members extending across the ditch and taking abutment on the planks on the respective opposite sides of the ditch, said planks being inserted at both sides of the ditch against drag plates being connected to and moving together with the excavating machine. 

1. Method for erecting a long straggling subterraneous construction within an open ditch comprising the steps of: excavating the earth at the front end of said ditch by means of a substantially continuously advanced excavating machine; propping the sidewalls of said ditch in the region adjacent and extending rearwardly from said front end by means of prop members on either side of said ditch, said prop members extending rearwardly from said excavating machine a predetermined distance and attached to said excavating machine for forward movement therewith; forming said construction sectionwise from prefabricated sections on the bottom of said ditch substantially within the free space interposed between said prop members, filling the space between the respective sidewalls of said ditch and said construction to thereby support the sidewalls of said ditch behind said prop members in the region from the bottom said ditch to the height of said construction, said space being formed behind said prop members as said excavating machine moves forward; inserting removable vertical planks along said sidewalls above said construction to thereby support said sidewalls of said ditch in the region from the top of said construction to the top of said ditch; and refilling the ditch above the construction.
 2. The method recited in claim 1 and further comprising the steps of: wedging the bottom ends of said vertical planks against the top of said construction; and bracing said planks adjacent the top of said ditch by means of stiffening members extending across said ditch between opposite sets of planks.
 3. The method recited in claim 2 and further comprising the steps of: removing said planks in the rearward regions of said ditch after said refilling step has been accomplished; filling the hollow spaces resulting from the removal of said planks; and transporting said planks forward to a position behind said excavating machine for reuse.
 4. The method recited in claim 1 wherein said refilling step is carried out substantially continuously in accordance with the advancement of said excavating Machine in the form of a ramp sloping from the rearward end of said ditch toward said front end of said ditch.
 5. The method recited in claim 1 and further comprising the steps of: prefabricating disassemblable sections of said construction at a location remote from said ditch; disassembling said construction sections into more easily transportable elements; transporting said elements to an assembly station in the vicinity of said ditch; and reassembling said parts to form prefabricated sections of said construction in preparation for the step of forming said construction in said ditch.
 6. Method in accordance with claim 1 in which said propping of the sidewalls of the ditch in the region rearwardly of a ditch section lying behind the prop members is arranged at least in a region of the ditch lying above said construction by means of vertical planks the lower ends of which are secured against the sidewalls of the ditch taking abutment on parts of the construction and the upper ends of which are secured against the sidewalls of the ditch by means of stiffening members extending across the ditch and taking abutment on the planks on the respective opposite sides of the ditch, said planks being inserted at both sides of the ditch against drag plates being connected to and moving together with the excavating machine. 